1. Field of the Invention
The invention relates to a railroad freight car, essentially including a loading platform and two wheelsets, two double-axle running gears or two bogies, the loading platform being cushioned against the wheelsets or the double-axle running gears or the loading platform with the bogie frame being cushioned against the wheelsets of the bogies by means of leaf suspension springs suspended by links from spring brackets, the guidance of the wheelsets or of the double-axle running gears below the loading platform or the guidance of the wheelsets into the bogie frame allowing a vertical displacement and limitedly horizontal out-turn of the wheelsets relative to the loading platform or to the bogie frame, respectively, or of the double-axle running gear relative to the loading platform.
Railroad freight cars having a loading platform, or so-called "flat cars", are known to have running gears which include single axles, double-axle running gears, or trucks or bogies. Such flat cars having a loading platform are conventionally loaded or unloaded by means of a crane or fork-lift truck. However, in order to provide for the economic loading or unloading of certain cargoes, for example of swap bodies or interchangeable containers standing on supporting legs, it is necessary to provide a device which allows the railroad freight car to receive or deposit the swap bodies or interchangeable containers automatically without loading appliances. The facility to alter the platform height, which is offered, for example, by the pneumatic suspension of bogies belonging to passenger train carriages, does not exist in railroad freight cars, since for economic reasons they are not equipped with trucks or bogies having pneumatic suspensions.
It is already known from practice, in the case of heavy-duty vehicles serving, in particular, for the transport of large transformers, to lower and raise the load mounting, including dump-in or scoop carriers, by means of hydraulic devices, and therefore to receive and deposit the load. However, those devices are very complex and can only be used in those complex heavy-duty transport vehicles which are equipped with dump-in or scoop carriers. It is further known to integrate into the loading platform of a railroad freight car a lift system, by means of which the railroad freight car is able to receive swap bodies or interchangeable containers. For that purpose, a truck transports the swap body or interchangeable container onto the stretch of rail, lowers it over the track, with the supporting legs of the swap body or interchangeable container extended, and drives back out of the track. A railroad car then rolls beneath the swap body or interchangeable container up to a defined take-up point. The lift structure of the railroad car is then raised, so that the supporting legs lose their contact with the ground and can be mechanically retracted. The train convoy, which is thus laden, can then leave the track. However, that system is very complex and expensive and is not suitable for economical traffic.
In addition, German Published, Non-Prosecuted Application DE 40 23 367 A has disclosed a railroad freight car essentially including a loading platform and two single axles or two double-axle running gears having fixedly clamped axles, wherein the loading platform is mounted on the single axle or the double-axle running gears by means of leaf suspension springs and the guidance of the single axles or of the double-axle running gear below the loading platform merely includes vertical guide elements or axle-bearing stems on the loading platform and the axle bearings of the single axle or the frame of the double-axle running gear, which enable a vertical displacement and a limitedly horizontal out-turn and transverse displacement of the single axle or double-axle running gear relative to the loading platform.
Lifting elements are disposed between the axle bearing housings of the single axle or the frame of the double-axle running gear and the leaf suspension springs. The loading platform with the leaf suspension springs can be raised relative to the single axle or to the double-axle running gear by means of the lifting elements. That construction enables railroad freight cars, having a running gear which includes single axles or double-axle running gears, to be economically constructed in such a way that the reception of swap bodies or interchangeable containers, in particular, is made possible without extraneous loading appliances. Nor is it necessary, for loading and unloading, to release any guys or guides between the loading platform and the running gear.
A drawback in the above-mentioned structure is the necessity to provide separate axle bearing housings for the axle bearings and separate spring buckles for the leaf suspension springs. A further drawback is the fact that the available installation space for the lifting elements is very small and, for that reason, a large amount of energy is consumed in order to raise the loading platform. A further drawback of that structure is the fact that the above-mentioned device cannot be used in railroad freight cars having running gears which include trucks or bogies, since between the loading bridge and the bogie frame a fixed connection is provided, by means of bogie pins or swivel rings, which is not releasable during operating usage.
2. Summary of the Invention
It is accordingly an object of the invention to provide a railroad freight car, which overcomes the hereinafore-mentioned disadvantages of the heretofore-known devices of this general type and which does so in such a way that, while using simple, economical means, a facility is provided for driving the railroad freight car beneath cargoes, especially swap bodies or interchangeable containers, for raising a loading platform and, following the reception of the cargo, for lowering the loading platform back into a travel position so as to enable the railroad freight car to be loaded and unloaded independently from loading appliances extraneous to the car, with the railroad freight car being able to be equipped with all standard conventional running gears, for example single axles, double-axle running gears, or trucks or bogies.
With the foregoing and other objects in view there is provided, in accordance with the invention, a railroad freight car, comprising a loading platform; two wheelsets, two double-axle running gears or two bogies having a bogie frame; spring brackets; leaf suspension springs; link suspension mountings suspending the leaf suspension springs from the spring brackets; the loading platform being cushioned against the wheelsets or the double-axle running gears or the loading platform with the bogie frame being cushioned against the wheelsets of the bogies by the leaf suspension springs; guidance of the wheelsets or of the double-axle running gears below the loading platform or guidance of the wheelsets into the bogie frame allowing a vertical displacement and limitedly horizontal out-turn of the wheelsets relative to the loading platform or to the bogie frame respectively or of the double-axle running gear relative to the loading platform; and lifting elements each being interposed between a respective one of the link suspension mountings and a respective one of the spring brackets of the loading platform or the bogie frame, for raising the loading platform relative to the wheelsets or to the double-axle running gear respectively or, with the bogie frame, relative to the wheelsets.
In accordance with another feature of the invention, the lifting element includes a lever which is hinge-mounted on the spring bracket and can be actuated by a drive mechanism.
In accordance with a further feature of the invention, the drive mechanism includes a hydraulic or pneumatic working cylinder, an electric motor or a mechanical gear system.
In accordance with an added feature of the invention, the lever is an angular lever which is hinge-mounted by a central pivot bearing on the spring bracket, and which is connected at one free end in an articulated manner to the suspension ring and at the other free end in an articulated manner to the drive mechanism. The invention enables railroad freight cars of the type stated in the introduction, having a running gear which includes single axles, double-axle running gears or bogies, to be economically constructed in such a way that the reception of swap bodies or interchangeable containers or extraneous loading appliances, in particular, is made possible. Nor is it necessary according to the invention, for the loading and unloading of the railroad freight car, to release any guys or guides between the loading platform and a running gear.
In accordance with an additional feature of the invention, the lever is a double lever and each single part of the double lever is mounted on a respective side of the spring bracket.
In accordance with yet another feature of the invention, the suspension rings are mounted on the lever by means of a link bolt, and when the loading platform is lowered, the link bolt bears with its contacting surface frontally against the spring bracket.
In accordance with yet a further feature of the invention, the link bolt has at least one transverse stop at a distance from its longitudinal ends, which is form-lockingly connected to the spring bracket, horizontally in the transverse direction of the vehicle, when the loading platform is lowered. A form-locking connection is one which connects two elements together due to the shape of the elements themselves, as opposed to a force-locking connection, which locks the elements together by force external to the elements.
In accordance with a concomitant feature of the invention, each of the link bolts has two spaced apart transverse stops, each bearing from one side against one of the spring brackets when the loading platform is lowered.
As a result of this configuration of the lever and of the link bolt and its configuration on the spring bracket, horizontal forces are kept away from the lever. The depositing of the load from the spring, through the suspension rings, onto the spring bracket, is reliably effected in the same form as in the case of suspension links mounted directly on the spring bracket.
All in all, by virtue of the invention, a simple and economical facility is provided for raising or lowering the entire loading platform of the railroad freight car relative to its running gears, irrespective of the type of running gears, and therefore a facility is provided for easily receiving and depositing swap bodies or interchangeable containers, in particular.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a railroad freight car, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.